there are a good reason not just thinking about what benefit that they can get. obviously they want Something can be controlled tracked easy , so they know all your information  by name,address,phone number all historical transaction would be evidence if something happened. thief,robber,fraud all kind of cyber crime can be easy to detected. that is  the main reason why some country still thinking about accepting kind of digital currency as their national currency. there is also another reason such as ordinary people not really understand the ways of digital currency they more likely the old ways is better than modern ways. i mean Real Money or something real to trade.